Endophytic Bacteria: Hidden Protective Associates of Plants against Biotic and Abiotic Stresses

  • Francisca I. OKUNGBOWA University of Benin, Department of Plant Biology and Biotechnology, Ugbowo, Benin City (NG)
  • Hakeem O. SHITTU University of Benin, Department of Plant Biology and Biotechnology, Ugbowo, Benin City (NG)
  • Henry O. OBIAZIKWOR University of Benin, Department of Plant Biology and Biotechnology, Ugbowo, Benin City (NG)
Keywords: bacteria; colonization; endophytes; gene - expression; protection; stress


An endophyte is a microorganism, usually bacterium or fungus, which lives within the internal tissue of a host plant, causing no apparent harm. Some characteristics of an endophyte include ability to promote plant growth and to confer plant tolerance to biotic and abiotic stresses. Endophytic bacteria spread across many phyla including the Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria. Endophytic bacteria are recruited by hosts and they get attached to the surface and eventually find their way into the internal tissues where they spread to the intercellular spaces of host plants. These bacteria have been isolated and characterized from different plants. Currently, culture-independent methods such as sequencing of the 16S rRNA gene or metalogenomics are used for identification and characterization of endophytes. The mechanisms by which the endophyte-induced plant protection is brought about can be through direct and/or indirect methods. The direct strategy antagonizes phytopathogens by the production of chemical substances while the indirect mechanisms improve resistance of hosts to pathogens. Global gene expression studies on some common endophytic bacteria implicated these direct and indirect strategies of bacterial-induced protection. More research should be geared towards how the economic importance of endophytic bacteria could be utilized to enhance global food security.


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How to Cite
OKUNGBOWA, F. I., SHITTU, H. O., & OBIAZIKWOR , H. O. (2019). Endophytic Bacteria: Hidden Protective Associates of Plants against Biotic and Abiotic Stresses. Notulae Scientia Biologicae, 11(2), 167-174. https://doi.org/10.15835/nsb11210423
Review articles
DOI: 10.15835/nsb11210423